Distributed and Rate-Adaptive Feature Compression
Aditya Deshmukh, Venugopal V. Veeravalli, Gunjan Verma
TL;DR
This work tackles distributed feature compression under variable communication rates for inference using pretrained models. For linear regressors, it proves that optimal distributed quantizers align with a one-dimensional projection of sensor data, enabling a simple, rate-adaptive scheme based on 1D clustering; it also introduces an adaptive mechanism that reduces bitrate without re-training. To extend to general models, the authors deploy a VQ-VAE framework that encodes sensor observations into low-dimensional latent codes, with end-to-end training fixed to the pretrained model and an adaptive scheme that reuses codebooks via weighted clustering. Experiments on synthetic data and benchmarks (MNIST Audio+Image, CIFAR-10) show the adaptive methods closely match or surpass non-adaptive baselines while substantially reducing communication load, highlighting practical impact for latency-sensitive, bandwidth-constrained deployments.
Abstract
We study the problem of distributed and rate-adaptive feature compression for linear regression. A set of distributed sensors collect disjoint features of regressor data. A fusion center is assumed to contain a pretrained linear regression model, trained on a dataset of the entire uncompressed data. At inference time, the sensors compress their observations and send them to the fusion center through communication-constrained channels, whose rates can change with time. Our goal is to design a feature compression {scheme} that can adapt to the varying communication constraints, while maximizing the inference performance at the fusion center. We first obtain the form of optimal quantizers assuming knowledge of underlying regressor data distribution. Under a practically reasonable approximation, we then propose a distributed compression scheme which works by quantizing a one-dimensional projection of the sensor data. We also propose a simple adaptive scheme for handling changes in communication constraints. We demonstrate the effectiveness of the distributed adaptive compression scheme through simulated experiments.
